Have you ever noticed the fuzzy growth (Fig1) on the underside of an oak or sycamore leaf and wondered what was wrong with the tree? Fuzzy mats of hairy growth on the underside of tree leaves (Fig 2) are often mistaken for a plant disease or insect problem. In actuality, the whitish-tan fuzzy growth is[Read More…]
Resources for landscapes and gardens in the Midwest
Landscape Report
Trees, Shrubs, Vines
It seems like yesterday that we were worried if Mother Nature’s faucet would ever stop (some of you still have that thought in some parts of the state). Now, in many parts of the state, soil moisture is all but gone after a few heat waves passed through the Midwest, with many plants that are[Read More…]
What is your go-to postemergence herbicide? If you answered Roundup (glyphosate is the active ingredient in Roundup), you would be in the majority for landscape and nursery professionals. Though glyphosate works very well on most weed species, there are times when other products may be more effective or offer a less phtytotoxic (damage to ornamental[Read More…]
Let’s get this out of the way….Plants and their ecosystems are amazing. To survive in so many environments with abundant or minimal resources without capabilities to migrate, plants are one of the most amazing organisms on the planet. Though research is abundant in above ground plant systems, below ground ecology is starting to show the[Read More…]
Ornamental dogwoods are prone to several leaf spot diseases, but the fungus, Septoria, is commonly found in Indiana. It causes angular, brown lesions bordered by a purplish color on the leaf. The leaf spot symptoms are similar to dogwood anthracnose, however, Septoria does not infect the twigs or branches so it is a much less[Read More…]
Fragrant sumac (Rhus aromatica) is a low growing native shrub that is valued for its adaptability to many soil types, wet or dry conditions, easy care as a ground cover, and for preventing erosion on slopes. It is often found in highway medians (Fig. 1), in parks or as a foundation planting around commercial buildings.[Read More…]
Don’t miss the 2019 Purdue Turf and Landscape Field Day on July 9th! Your opportunity to interact with Purdue Specialists, see the latest on-going research and best management practices, and network with others in the Green Industry. This is the premiere Green Industry education event that you’ll find this summer! https://www.mrtf.org/event/turf-and-landscape-field-day/?event_date=2019-07-09 In the landscape track,[Read More…]
Although most cities contain an Elm Street, very few cities can claim having mature American elms on that street, or any other. The American elm was a premier street tree: Tolerant of compacted soil, fast growing, long-lived, and with a beautiful vase-shaped form. It’s very popularity led to its downfall. The introduction of Dutch elm[Read More…]
Like anthracnose diseases of other shade trees, sycamore anthracnose is a very common occurrence in the landscape (Figure 1). Symptoms of sycamore anthracnose normally develop as small spots or dead areas centered along the veins of leaves or along leaf margins (Figure 2). Under conducive conditions these spots expand, killing more leaf tissue and causing[Read More…]
Introduction The Colorado Blue spruce is not native to Indiana and tends to be susceptible to disease. One common disease, caused by the fungus Rizosphaera kalkhoffii, results in the defoliation of the tree. If left untreated needlecast can lead to the death of the tree. Symptoms and Signs Symptoms of needlecast don’t develop until two[Read More…]
Sudden oak death, as the name suggests, is a disease that is capable of rapidly killing certain species of oaks. It was first identified in California, in 1995. Two years earlier it was identified in Germany and the Netherlands, killing rhododendron. Because the pathogen originally infected and killed tanoaks, an undesirable, understory scrub tree, it[Read More…]
Although most people are understandably concerned about boxwood blight, boxwood does suffer from a number of diseases, including Volutella blight and Macrophoma leaf spot. Unfortunately, boxwood also suffers from a stem decline, caused by Colletotrichum theobromicola. The following was written by Dr. Raj Singh, LSU. Boxwood Stem Decline by Dr. Raj Singh Available on line[Read More…]
A question that I often receive goes something like…. ‘How do I control grassy weeds in liriope and iris?’ At first glance, it would appear that those ornamental plants are very similar to grasses, but looks may be deceiving as they are actually not grasses. We know that broadleaf weeds can be controlled in grasses[Read More…]
Oak leaf blister is caused by the fungus Taphrina caerulescens. Infections occur as buds swell and open during wet, spring conditions. Leaf blister symptoms usually appear within several weeks following infection as 1/4-1/2 inch circular, light green bulges on the top surface of leaves.(Fig 1) From the underside, the affected areas are sunken or depressed. These[Read More…]
Q: I’ve attached pictures of the only tree we have on our property. Because it is our only tree, I am deeply concerned with the possibilities of irreparable damage to it. As you can see, one of the branches broke off during a November windstorm. Unfortunately, that left a bare gap on the trunk. Please[Read More…]
We all know that plants take up nitrogen in significant quantities, compared to some of the other essential nutrients. What most don’t know is that elemental nitrogen (N) is not what is taken up by plants. In fact, nitrogen can be taken up in only two forms, ammonium (NH4) and nitrate (NO3). Fertilizer labels will[Read More…]
Sign-up to receive email news and alerts from Purdue Landscape Working Group:
